[PATCH 3/4] Support 'info proc' for native FreeBSD processes.

John Baldwin
2017-12-22T22:05:50Z

- Command line arguments are fetched via the kern.proc.args.<pid>
sysctl.
- The 'cwd' and 'exe' values are obtained from the per-process
file descriptor table returned by kinfo_getfile() from libutil.
- 'mappings' is implemented by walking the array of VM map entries
returned by kinfo_getvmmap() from libutil.
- 'stat' and 'status' output is generated by outputting fields from
the structure returned by the kern.proc.pid.<pid> sysctl.

gdb/ChangeLog:

* configure.ac: Check for kinfo_getfile in libutil.
* configure: Regenerate.
* config.in: Regenerate.
* fbsd-nat.c: Include "fbsd-tdep.h".
(fbsd_fetch_cmdline): New.
(fbsd_fetch_kinfo_proc): Move earlier and change to return a bool
rather than calling error.
(fbsd_info_proc): New.
(fbsd_thread_name): Report error if fbsd_fetch_kinfo_proc fails.
(fbsd_wait): Report warning if fbsd_fetch_kinfo_proc fails.
(fbsd_nat_add_target): Set "to_info_proc" to "fbsd_info_proc".
---
gdb/ChangeLog | 14 ++
gdb/config.in | 3 +
gdb/configure | 60 +++++++++
gdb/configure.ac | 5 +
gdb/fbsd-nat.c | 404 +++++++++++++++++++++++++++++++++++++++++++++++++++----
5 files changed, 462 insertions(+), 24 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2311749de7..3d580c1c9e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,17 @@
+2017-12-22 John Baldwin <jhb@FreeBSD.org>
+
+ * configure.ac: Check for kinfo_getfile in libutil.
+ * configure: Regenerate.
+ * config.in: Regenerate.
+ * fbsd-nat.c: Include "fbsd-tdep.h".
+ (fbsd_fetch_cmdline): New.
+ (fbsd_fetch_kinfo_proc): Move earlier and change to return a bool
+ rather than calling error.
+ (fbsd_info_proc): New.
+ (fbsd_thread_name): Report error if fbsd_fetch_kinfo_proc fails.
+ (fbsd_wait): Report warning if fbsd_fetch_kinfo_proc fails.
+ (fbsd_nat_add_target): Set "to_info_proc" to "fbsd_info_proc".
+
2017-12-22 John Baldwin <jhb@FreeBSD.org>

* fbsd-tdep.c (KVE_STRUCTSIZE, KVE_START, KVE_END, KVE_OFFSET)
diff --git a/gdb/config.in b/gdb/config.in
index 1d11a97080..ad2cc1754e 100644
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -219,6 +219,9 @@
/* Define to 1 if you have the <inttypes.h> header file. */
#undef HAVE_INTTYPES_H

+/* Define to 1 if your system has the kinfo_getfile function. */
+#undef HAVE_KINFO_GETFILE
+
/* Define to 1 if your system has the kinfo_getvmmap function. */
#undef HAVE_KINFO_GETVMMAP

diff --git a/gdb/configure b/gdb/configure
index 7b250079de..a0baa7a53a 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -7927,6 +7927,66 @@ $as_echo "#define HAVE_KINFO_GETVMMAP 1" >>confdefs.h
fi

+# fbsd-nat.c can also use kinfo_getfile.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing kinfo_getfile" >&5
+$as_echo_n "checking for library containing kinfo_getfile... " >&6; }
+if test "${ac_cv_search_kinfo_getfile+set}" = set; then :
+ $as_echo_n "(cached) " >&6
+else
+ ac_func_search_save_LIBS=$LIBS
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+/* Override any GCC internal prototype to avoid an error.
+ Use char because int might match the return type of a GCC
+ builtin and then its argument prototype would still apply. */
+#ifdef __cplusplus
+extern "C"
+#endif
+char kinfo_getfile ();
+int
+main ()
+{
+return kinfo_getfile ();
+ ;
+ return 0;
+}
+_ACEOF
+for ac_lib in '' util util-freebsd; do
+ if test -z "$ac_lib"; then
+ ac_res="none required"
+ else
+ ac_res=-l$ac_lib
+ LIBS="-l$ac_lib $ac_func_search_save_LIBS"
+ fi
+ if ac_fn_c_try_link "$LINENO"; then :
+ ac_cv_search_kinfo_getfile=$ac_res
+fi
+rm -f core conftest.err conftest.$ac_objext \
+ conftest$ac_exeext
+ if test "${ac_cv_search_kinfo_getfile+set}" = set; then :
+ break
+fi
+done
+if test "${ac_cv_search_kinfo_getfile+set}" = set; then :
+
+else
+ ac_cv_search_kinfo_getfile=no
+fi
+rm conftest.$ac_ext
+LIBS=$ac_func_search_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_kinfo_getfile" >&5
+$as_echo "$ac_cv_search_kinfo_getfile" >&6; }
+ac_res=$ac_cv_search_kinfo_getfile
+if test "$ac_res" != no; then :
+ test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
+
+$as_echo "#define HAVE_KINFO_GETFILE 1" >>confdefs.h
+
+fi
+
+

if test "X$prefix" = "XNONE"; then
acl_final_prefix="$ac_default_prefix"
diff --git a/gdb/configure.ac b/gdb/configure.ac
index 8e706b6e27..96ec77e0af 100644
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -523,6 +523,11 @@ AC_SEARCH_LIBS(kinfo_getvmmap, util util-freebsd,
[AC_DEFINE(HAVE_KINFO_GETVMMAP, 1,
[Define to 1 if your system has the kinfo_getvmmap function. ])])

+# fbsd-nat.c can also use kinfo_getfile.
+AC_SEARCH_LIBS(kinfo_getfile, util util-freebsd,
+ [AC_DEFINE(HAVE_KINFO_GETFILE, 1,
+ [Define to 1 if your system has the kinfo_getfile function. ])])
+
AM_ICONV

# GDB may fork/exec the iconv program to get the list of supported character
diff --git a/gdb/fbsd-nat.c b/gdb/fbsd-nat.c
index 29b7ee5e33..e460c23d95 100644
--- a/gdb/fbsd-nat.c
+++ b/gdb/fbsd-nat.c
@@ -32,14 +32,16 @@
#include <sys/signal.h>
#include <sys/sysctl.h>
#include <sys/user.h>
-#ifdef HAVE_KINFO_GETVMMAP
+#if defined(HAVE_KINFO_GETFILE) || defined(HAVE_KINFO_GETVMMAP)
#include <libutil.h>
-#else
+#endif
+#if !defined(HAVE_KINFO_GETVMMAP)
#include "filestuff.h"
#endif

#include "elf-bfd.h"
#include "fbsd-nat.h"
+#include "fbsd-tdep.h"

#include

@@ -77,7 +79,7 @@ fbsd_pid_to_exec_file (struct target_ops *self, int pid)
return NULL;
}

-#ifdef HAVE_KINFO_GETVMMAP
+#if defined(HAVE_KINFO_GETFILE) || defined(HAVE_KINFO_GETVMMAP)
/* Deleter for std::unique_ptr that invokes free. */

template <typename T>
@@ -85,7 +87,9 @@ struct free_deleter
{
void operator() (T *ptr) const { free (ptr); }
};
+#endif

+#ifdef HAVE_KINFO_GETVMMAP
/* Iterate over all the memory regions in the current inferior,
calling FUNC for each memory region. OBFD is passed as the last
argument to FUNC. */
@@ -210,6 +214,369 @@ fbsd_find_memory_regions (struct target_ops *self,
}
#endif

+/* Fetch the command line for a running process. */
+
+static gdb::unique_xmalloc_ptr<char>
+fbsd_fetch_cmdline (pid_t pid)
+{
+ size_t len;
+ int mib[4];
+
+ len = 0;
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_PROC;
+ mib[2] = KERN_PROC_ARGS;
+ mib[3] = pid;
+ if (sysctl (mib, 4, NULL, &len, NULL, 0) == -1)
+ return nullptr;
+
+ gdb::unique_xmalloc_ptr<char> cmdline ((char *) xmalloc (len));
+ if (sysctl (mib, 4, cmdline.get (), &len, NULL, 0) == -1)
+ return nullptr;
+
+ return cmdline;
+}
+
+/* Fetch the external variant of the kernel's internal process
+ structure for the process PID into KP. */
+
+static bool
+fbsd_fetch_kinfo_proc (pid_t pid, struct kinfo_proc *kp)
+{
+ size_t len;
+ int mib[4];
+
+ len = sizeof *kp;
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_PROC;
+ mib[2] = KERN_PROC_PID;
+ mib[3] = pid;
+ return (sysctl (mib, 4, kp, &len, NULL, 0) == 0);
+}
+
+/* Implement the "to_info_proc target_ops" method. */
+
+static void
+fbsd_info_proc (struct target_ops *ops, const char *args,
+ enum info_proc_what what)
+{
+#ifdef HAVE_KINFO_GETFILE
+ std::unique_ptr<struct kinfo_file, free_deleter<struct kinfo_file>> fdtbl;
+ int nfd = 0;
+#endif
+ struct kinfo_proc kp;
+ char *tmp;
+ pid_t pid;
+ bool do_cmdline = false;
+ bool do_cwd = false;
+ bool do_exe = false;
+#ifdef HAVE_KINFO_GETVMMAP
+ bool do_mappings = false;
+#endif
+ bool do_status = false;
+ bool do_stat = false;
+ bool kp_valid = false;
+
+ switch (what)
+ {
+ case IP_MINIMAL:
+ do_cmdline = true;
+ do_cwd = true;
+ do_exe = true;
+ break;
+#ifdef HAVE_KINFO_GETVMMAP
+ case IP_MAPPINGS:
+ do_mappings = true;
+ break;
+#endif
+ case IP_STATUS:
+ do_status = true;
+ break;
+ case IP_STAT:
+ do_stat = true;
+ break;
+ case IP_CMDLINE:
+ do_cmdline = true;
+ break;
+ case IP_EXE:
+ do_exe = true;
+ break;
+ case IP_CWD:
+ do_cwd = true;
+ break;
+ case IP_ALL:
+ do_cmdline = true;
+ do_cwd = true;
+ do_exe = true;
+#ifdef HAVE_KINFO_GETVMMAP
+ do_mappings = true;
+#endif
+ do_status = true;
+ do_stat = true;
+ break;
+ default:
+ error (_("Not supported on this target."));
+ }
+
+ gdb_argv built_argv (args);
+ if (built_argv.count () == 0)
+ {
+ pid = ptid_get_pid (inferior_ptid);
+ if (pid == 0)
+ error (_("No current process: you must name one."));
+ }
+ else
+ {
+ pid = strtol (built_argv[0], NULL, 10);
+ }
+
+ printf_filtered (_("process %d\n"), pid);
+#ifdef HAVE_KINFO_GETFILE
+ if (do_cwd || do_exe)
+ fdtbl.reset (kinfo_getfile (pid, &nfd));
+#endif
+ if (do_stat || do_status)
+ {
+ kp_valid = fbsd_fetch_kinfo_proc(pid, &kp);
+ if (!kp_valid)
+ warning (_("Failed to fetch process information"));
+ }
+
+ if (do_cmdline)
+ {
+ gdb::unique_xmalloc_ptr<char> cmdline = fbsd_fetch_cmdline (pid);
+ if (cmdline)
+ printf_filtered ("cmdline = '%s'\n", cmdline.get ());
+ else
+ warning (_("unable to fetch command line"));
+ }
+ if (do_cwd)
+ {
+ const char *cwd = NULL;
+#ifdef HAVE_KINFO_GETFILE
+ struct kinfo_file *kf = fdtbl.get ();
+ for (int i = 0; i < nfd; i++, kf++)
+ {
+ if (kf->kf_type == KF_TYPE_VNODE && kf->kf_fd == KF_FD_TYPE_CWD)
+ {
+ cwd = kf->kf_path;
+ break;
+ }
+ }
+#endif
+ if (cwd)
+ printf_filtered ("cwd = '%s'\n", cwd);
+ else
+ warning (_("unable to fetch current working directory"));
+ }
+ if (do_exe)
+ {
+ const char *exe = NULL;
+#ifdef HAVE_KINFO_GETFILE
+ struct kinfo_file *kf = fdtbl.get ();
+ for (int i = 0; i < nfd; i++, kf++)
+ {
+ if (kf->kf_type == KF_TYPE_VNODE && kf->kf_fd == KF_FD_TYPE_TEXT)
+ {
+ exe = kf->kf_path;
+ break;
+ }
+ }
+#endif
+ if (exe == NULL)
+ exe = fbsd_pid_to_exec_file (ops, pid);
+ if (exe)
+ printf_filtered ("exe = '%s'\n", exe);
+ else
+ warning (_("unable to fetch executable path name"));
+ }
+#ifdef HAVE_KINFO_GETVMMAP
+ if (do_mappings)
+ {
+ int nvment;
+ std::unique_ptr<struct kinfo_vmentry, free_deleter<struct kinfo_vmentry>>
+ vmentl (kinfo_getvmmap (pid, &nvment));
+
+ if (vmentl)
+ {
+ printf_filtered (_("Mapped address spaces:\n\n"));
+#ifdef __LP64__
+ printf_filtered (" %18s %18s %10s %10s %9s %s\n",
+ "Start Addr",
+ " End Addr",
+ " Size", " Offset", "Flags ", "File");
+#else
+ printf_filtered ("\t%10s %10s %10s %10s %9s %s\n",
+ "Start Addr",
+ " End Addr",
+ " Size", " Offset", "Flags ", "File");
+#endif
+
+ struct kinfo_vmentry *kve = vmentl.get ();
+ for (int i = 0; i < nvment; i++, kve++)
+ {
+ ULONGEST start, end;
+
+ start = kve->kve_start;
+ end = kve->kve_end;
+#ifdef __LP64__
+ printf_filtered (" %18s %18s %10s %10s %9s %s\n",
+ hex_string (start),
+ hex_string (end),
+ hex_string (end - start),
+ hex_string (kve->kve_offset),
+ fbsd_vm_map_entry_flags (kve->kve_flags,
+ kve->kve_protection),
+ kve->kve_path);
+#else
+ printf_filtered ("\t%10s %10s %10s %10s %9s %s\n",
+ hex_string (start),
+ hex_string (end),
+ hex_string (end - start),
+ hex_string (kve->kve_offset),
+ fbsd_vm_map_entry_flags (kve->kve_flags,
+ kve->kve_protection),
+ kve->kve_path);
+#endif
+ }
+ }
+ else
+ warning (_("unable to fetch virtual memory map"));
+ }
+#endif
+ if (do_status && kp_valid)
+ {
+ const char *state;
+ int pgtok;
+
+ printf_filtered ("Name:\t%s\n", kp.ki_comm);
+ switch (kp.ki_stat)
+ {
+ case SIDL:
+ state = "I (idle)";
+ break;
+ case SRUN:
+ state = "R (running)";
+ break;
+ case SSTOP:
+ state = "T (stopped)";
+ break;
+ case SZOMB:
+ state = "Z (zombie)";
+ break;
+ case SSLEEP:
+ state = "S (sleeping)";
+ break;
+ case SWAIT:
+ state = "W (interrupt wait)";
+ break;
+ case SLOCK:
+ state = "L (blocked on lock)";
+ break;
+ default:
+ state = "? (unknown)";
+ break;
+ }
+ printf_filtered ("State:\t%s\n", state);
+ printf_filtered ("Pid:\t%d\n", kp.ki_pid);
+ printf_filtered ("PPid:\t%d\n", kp.ki_ppid);
+ printf_filtered ("Uid:\t%d %d %d\n", kp.ki_ruid, kp.ki_uid, kp.ki_svuid);
+ printf_filtered ("Gid:\t%d %d %d\n", kp.ki_rgid, kp.ki_groups[0],
+ kp.ki_svgid);
+ printf_filtered ("Groups:\t");
+ for (int i = 0; i < kp.ki_ngroups; i++)
+ printf_filtered ("%d ", kp.ki_groups[i]);
+ printf_filtered ("\n");
+ pgtok = getpagesize () / 1024;
+ printf_filtered ("VmSize:\t%8ju kB\n", (uintmax_t) kp.ki_size / 1024);
+ printf_filtered ("VmRSS:\t%8ju kB\n", (uintmax_t) kp.ki_rssize * pgtok);
+ printf_filtered ("VmData:\t%8ju kB\n", (uintmax_t) kp.ki_dsize * pgtok);
+ printf_filtered ("VmStk:\t%8ju kB\n", (uintmax_t) kp.ki_ssize * pgtok);
+ printf_filtered ("VmExe:\t%8ju kB\n", (uintmax_t) kp.ki_tsize * pgtok);
+ printf_filtered ("SigPnd:\t");
+ for (int i = 0; i < _SIG_WORDS; i++)
+ printf_filtered ("%08x ", kp.ki_siglist.__bits[i]);
+ printf_filtered ("\n");
+ printf_filtered ("SigIgn:\t");
+ for (int i = 0; i < _SIG_WORDS; i++)
+ printf_filtered ("%08x ", kp.ki_sigignore.__bits[i]);
+ printf_filtered ("\n");
+ printf_filtered ("SigCgt:\t");
+ for (int i = 0; i < _SIG_WORDS; i++)
+ printf_filtered ("%08x ", kp.ki_sigcatch.__bits[i]);
+ printf_filtered ("\n");
+ }
+ if (do_stat && kp_valid)
+ {
+ char state;
+ int pgtok;
+
+ printf_filtered ("Exec file: %s\n", kp.ki_comm);
+ switch (kp.ki_stat)
+ {
+ case SIDL:
+ state = 'I';
+ break;
+ case SRUN:
+ state = 'R';
+ break;
+ case SSTOP:
+ state = 'T';
+ break;
+ case SZOMB:
+ state = 'Z';
+ break;
+ case SSLEEP:
+ state = 'S';
+ break;
+ case SWAIT:
+ state = 'W';
+ break;
+ case SLOCK:
+ state = 'L';
+ break;
+ default:
+ state = '?';
+ break;
+ }
+ printf_filtered ("State: %c\n", state);
+ printf_filtered ("Parent process: %d\n", kp.ki_ppid);
+ printf_filtered ("Process group: %d\n", kp.ki_pgid);
+ printf_filtered ("Session id: %d\n", kp.ki_sid);
+ printf_filtered ("TTY: %ju\n", (uintmax_t) kp.ki_tdev);
+ printf_filtered ("TTY owner process group: %d\n", kp.ki_tpgid);
+ printf_filtered ("Minor faults (no memory page): %ld\n",
+ kp.ki_rusage.ru_minflt);
+ printf_filtered ("Minor faults, children: %ld\n",
+ kp.ki_rusage_ch.ru_minflt);
+ printf_filtered ("Major faults (memory page faults): %ld\n",
+ kp.ki_rusage.ru_majflt);
+ printf_filtered ("Major faults, children: %ld\n",
+ kp.ki_rusage_ch.ru_majflt);
+ printf_filtered ("utime: %jd.%06ld\n",
+ (intmax_t) kp.ki_rusage.ru_utime.tv_sec,
+ kp.ki_rusage.ru_utime.tv_usec);
+ printf_filtered ("stime: %jd.%06ld\n",
+ (intmax_t) kp.ki_rusage.ru_stime.tv_sec,
+ kp.ki_rusage.ru_stime.tv_usec);
+ printf_filtered ("utime, children: %jd.%06ld\n",
+ (intmax_t) kp.ki_rusage_ch.ru_utime.tv_sec,
+ kp.ki_rusage_ch.ru_utime.tv_usec);
+ printf_filtered ("stime, children: %jd.%06ld\n",
+ (intmax_t) kp.ki_rusage_ch.ru_stime.tv_sec,
+ kp.ki_rusage_ch.ru_stime.tv_usec);
+ printf_filtered ("'nice' value: %d\n", kp.ki_nice);
+ printf_filtered ("start time: %jd.%06ld\n", kp.ki_start.tv_sec,
+ kp.ki_start.tv_usec);
+ pgtok = getpagesize () / 1024;
+ printf_filtered ("Virtual memory size: %ju kB\n",
+ (uintmax_t) kp.ki_size / 1024);
+ printf_filtered ("Resident set size: %ju kB\n",
+ (uintmax_t) kp.ki_rssize * pgtok);
+ printf_filtered ("rlim: %ju kB\n", (uintmax_t) kp.ki_rusage.ru_maxrss);
+ }
+}
+
#ifdef KERN_PROC_AUXV
static enum target_xfer_status (*super_xfer_partial) (struct target_ops *ops,
enum target_object object,
@@ -461,23 +828,6 @@ show_fbsd_lwp_debug (struct ui_file *file, int from_tty,
}

#if defined(TDP_RFPPWAIT) || defined(HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME)
-/* Fetch the external variant of the kernel's internal process
- structure for the process PID into KP. */
-
-static void
-fbsd_fetch_kinfo_proc (pid_t pid, struct kinfo_proc *kp)
-{
- size_t len;
- int mib[4];
-
- len = sizeof *kp;
- mib[0] = CTL_KERN;
- mib[1] = KERN_PROC;
- mib[2] = KERN_PROC_PID;
- mib[3] = pid;
- if (sysctl (mib, 4, kp, &len, NULL, 0) == -1)
- perror_with_name (("sysctl"));
-}
#endif

/*
@@ -565,7 +915,8 @@ fbsd_thread_name (struct target_ops *self, struct thread_info *thr)
/* Note that ptrace_lwpinfo returns the process command in pl_tdname
if a name has not been set explicitly. Return a NULL name in
that case. */
- fbsd_fetch_kinfo_proc (pid, &kp);
+ if (!fbsd_fetch_kinfo_proc (pid, &kp))
+ perror_with_name (_("Failed to fetch process information"));
if (ptrace (PT_LWPINFO, lwp, (caddr_t) &pl, sizeof pl) == -1)
perror_with_name (("ptrace"));
if (strcmp (kp.ki_comm, pl.pl_tdname) == 0)
@@ -975,9 +1326,13 @@ fbsd_wait (struct target_ops *ops,
#ifndef PTRACE_VFORK
/* For vfork, the child process will have the P_PPWAIT
flag set. */
- fbsd_fetch_kinfo_proc (child, &kp);
- if (kp.ki_flag & P_PPWAIT)
- ourstatus->kind = TARGET_WAITKIND_VFORKED;
+ if (fbsd_fetch_kinfo_proc (child, &kp))
+ {
+ if (kp.ki_flag & P_PPWAIT)
+ ourstatus->kind = TARGET_WAITKIND_VFORKED;
+ }
+ else
+ warning (_("Failed to fetch process information"));
#endif
ourstatus->value.related_pid = child_ptid;

@@ -1181,6 +1536,7 @@ fbsd_nat_add_target (struct target_ops *t)
{
t->to_pid_to_exec_file = fbsd_pid_to_exec_file;
t->to_find_memory_regions = fbsd_find_memory_regions;
+ t->to_info_proc = fbsd_info_proc;
#ifdef KERN_PROC_AUXV
super_xfer_partial = t->to_xfer_partial;
t->to_xfer_partial = fbsd_xfer_partial;
--
2.15.1